Glomerulonephritis is a group of kidney conditions characterized by inflammation within the kidney’s filtering units. This inflammation can disrupt the kidney’s ability to effectively remove waste products and excess fluids from the body. Understanding whether the body’s own immune system contributes to this damage is important for clarity on this complex condition.
Understanding Glomerulonephritis
Glomerulonephritis targets the glomeruli, tiny, intricate networks of blood vessels within the kidneys. Each kidney contains approximately one million nephrons, each with a glomerulus. Glomeruli function as primary filtration units, allowing smaller molecules, waste products, and excess fluid to pass through their thin walls while retaining larger molecules like proteins and blood cells within the bloodstream.
When these delicate filtering units become inflamed, their function is impaired. This damage allows substances that should remain in the blood, such as proteins and red blood cells, to leak into the urine. Consequently, waste products and excess fluid accumulate in the body, leading to various symptoms and potentially compromising overall kidney function.
Understanding Autoimmune Diseases
Autoimmune diseases occur when the body’s immune system, designed to protect against foreign invaders, mistakenly attacks its own healthy tissues. Normally, the immune system distinguishes between “self” (the body’s own cells) and “non-self” (harmful pathogens). In an autoimmune response, this recognition system malfunctions.
The immune system produces antibodies or immune cells that target and damage the body’s own organs or tissues. This misguided attack can lead to inflammation and damage. The specific symptoms and affected organs depend on which tissues the immune system targets.
The Autoimmune Connection to Glomerulonephritis
Some forms of glomerulonephritis are autoimmune, meaning the body’s immune system directly attacks the kidney’s filtering units. In these cases, the immune system incorrectly identifies components of the glomeruli as foreign invaders, leading to an immune response where antibodies or immune cells are deployed against them, causing inflammation and subsequent damage.
For example, systemic lupus erythematosus (SLE), a chronic inflammatory autoimmune disease, can affect various parts of the body, including the kidneys, and is a known cause of autoimmune glomerulonephritis. Another example is Goodpasture’s syndrome, a rare disorder where the immune system produces antibodies specifically against tissues in both the lungs and kidneys, leading to progressive damage to the glomeruli. The presence of these autoantibodies or immune cell infiltration contributes to the inflammation and scarring observed in the glomeruli, hindering their ability to filter blood effectively.
Other Causes of Glomerulonephritis
While autoimmune processes are a significant cause for some forms of glomerulonephritis, not all cases stem from an immune system malfunction. Infections are a common cause, such as post-streptococcal glomerulonephritis, which can develop a week or two after a streptococcal infection.
Certain medications or other underlying medical conditions, distinct from autoimmune disorders, can also lead to glomerulonephritis. High blood pressure, if poorly managed over a long period, can contribute to scarring and inflammation of the glomeruli. Similarly, diabetic kidney disease, resulting from elevated blood sugar levels, can cause damage to these filtering units.